<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        .box {
            width: 600px;
            height: 500px;
            border: 1px solid black;
            background: pink;
            margin: 0 auto;
            position: relative;
        }
        
        .son1 {
            width: 50px;
            height: 50px;
            border: 1px solid #222;
            background-color: skyblue;
            position: absolute;
            left: 0;
            top: 225px;
        }
        
        .son2 {
            width: 50px;
            height: 50px;
            border: 1px solid #222;
            background-color: slateblue;
            position: absolute;
            right: 0;
            bottom: 225px;
        }
    </style>
</head>

<body>
    <div class="box">
        <div class="son1">大毛</div>
        <div class="son2">二毛</div>
    </div>
</body>

</html>